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%I #25 Apr 21 2019 03:00:22
%S 16,24,36,40,54,56,60,81,84,88,90,100,104,126,132,135,136,140,150,152,
%T 156,184,189,196,198,204,220,225,228,232,234,248,250,260,276,294,296,
%U 297,306,308,315,328,340,342,344,348,350,351,364,372,375,376,380,414
%N Products of four primes, not all distinct.
%C Numbers with exactly four prime factors (counted with multiplicity) but fewer than four distinct prime factors.
%C Numbers n such that bigomega(n) = 4 and omega(n) < 4.
%H Kalle Siukola, <a href="/A307341/b307341.txt">Table of n, a(n) for n = 1..10000</a>
%o (Python 3)
%o import sympy
%o def bigomega(n): return sympy.primeomega(n)
%o def omega(n): return len(sympy.primefactors(n))
%o print([n for n in range(1, 1000) if bigomega(n) == 4 and omega(n) < 4])
%o (PARI) isok(n) = (bigomega(n) == 4) && (omega(n) < 4); \\ _Michel Marcus_, Apr 03 2019
%Y Setwise difference of A014613 and A046386.
%Y Union of A030514, A065036, A085986 and A085987.
%K easy,nonn
%O 1,1
%A _Kalle Siukola_, Apr 02 2019
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